BackgroundThere is no vaccine against the major global pathogen Chlamydia trachomatis; its different serovars cause trachoma in the eye or chlamydia in the genital tract. We did a clinical trial administering CTH522, a recombinant version of the C trachomatis major outer membrane molecule, in different dose concentrations with and without adjuvant, to establish its safety and immunogenicity when administered intramuscularly, intradermally, and topically into the eye, in prime-boost regimens.MethodsCHLM-02 was a phase 1, double-blind, randomised, placebo-controlled trial at the National Institute for Health Research Imperial Clinical Research Facility, London, UK. Participants were healthy men and non-pregnant women aged 18–45 years, without pre-existing C trachomatis genital infection. Participants were assigned into six groups by the electronic database in a pre-prepared randomisation list (A–F). Participants were randomly assigned (1:1:1:1:1) to each of the groups A–E (12 participants each) and 6 were randomly assigned to group F. Investigators were masked to treatment allocation. Groups A–E received investigational medicinal product and group F received placebo only. Two liposomal adjuvants were compared, CAF01 and CAF09b. The groups were intramuscular 85 μg CTH522-CAF01, or placebo on day 0 and two boosters or placebo at day 28 and 112, and a mucosal recall with either placebo or CTH522 topical ocularly at day 140 (A); intramuscular 85 μg CTH522-CAF01, two boosters at day 28 and 112 with additional topical ocular administration of CTH522, and a mucosal recall with either placebo or CTH522 topical ocularly at day 140 (B); intramuscular 85 μg CTH522-CAF01, two boosters at day 28 and 112 with additional intradermal administration of CTH522, and a mucosal recall with either placebo or CTH522 topical ocularly at day 140 (C); intramuscular 15 μg CTH522-CAF01, two boosters at day 28 and 112, and a mucosal recall with either placebo or CTH522 topical ocularly at day 140 (D); intramuscular 85 μg CTH522-CAF09b, two boosters at day 28 and 112, and a mucosal recall with either placebo or CTH522 topical ocularly at day 140 (E); intramuscular placebo (F). The primary outcome was safety; the secondary outcome (humoral immunogenicity) was the percentage of trial participants achieving anti-CTH522 IgG seroconversion, defined as four-fold and ten-fold increase over baseline concentrations. Analyses were done as intention to treat and as per protocol. The trial is registered with ClinicalTrials.gov, NCT03926728, and is complete.FindingsBetween Feb 17, 2020 and Feb 22, 2022, of 154 participants screened, 65 were randomly assigned, and 60 completed the trial (34 [52%] of 65 women, 46 [71%] of 65 White, mean age 26·8 years). No serious adverse events occurred but one participant in group A2 discontinued dosing after having self-limiting adverse events after both placebo and investigational medicinal product doses. Study procedures were otherwise well tolerated; the majority of adverse events were mild to moderate, with only seven (1%) of 865 reported as grade 3 (severe). There was 100% four-fold seroconversion rate by day 42 in the active groups (A–E) and no seroconversion in the placebo group. Serum IgG anti-CTH522 titres were higher after 85 μg CTH522-CAF01 than 15 μg, although not significantly (intention-to-treat median IgG titre ratio groups A–C:D=5·6; p=0·062), with no difference after three injections of 85 μg CTH522-CAF01 compared with CTH522-CAF09b (group E). Intradermal CTH522 (group C) induced high titres of serum IgG anti-CTH522 neutralising antibodies against serovars B (trachoma) and D (urogenital). Topical ocular CTH522 (group B) at day 28 and 112 induced higher total ocular IgA compared with baseline (p<0·001). Participants in all active vaccine groups, particularly groups B and E, developed cell mediated immune responses against CTH522.InterpretationCTH522, adjuvanted with CAF01 or CAF09b, is safe and immunogenic, with 85 μg CTH522-CAF01 inducing robust serum IgG binding titres. Intradermal vaccination conferred systemic IgG neutralisation breadth, and topical ocular administration increased ocular IgA formation. These findings indicate CTH522 vaccine regimens against ocular trachoma and urogenital chlamydia for testing in phase 2, clinical trials.FundingThe EU Horizon Program TRACVAC.
Two malaria transmission-blocking vaccine (TBV) candidates, R0.6C and ProC6C, have completed preclinical development including the selection of adjuvants, Alhydrogel® with or without the saponin based adjuvant Matrix-M™. Here, we report on the final drug product (formulation) design of R0.6C and ProC6C and evaluate their safety and biochemical stability in preparation for preclinical and clinical pharmacy handling. The point-of-injection stability studies demonstrated that both the R0.6C and ProC6C antigens are stable on Alhydrogel in the presence or absence of Matrix-M for up to 24 h at room temperature. As this is the first study to combine Alhydrogel and Matrix-M for clinical use, we also evaluated their potential interactions. Matrix-M adsorbs to Alhydrogel, while not displacing the > 95 % adsorbed protein. The R0.6C and ProC6C formulations were found to be safe and well tolerated in repeated dose toxicity studies in rabbits generating high levels of functional antibodies that blocked infection of mosquitoes. Further, the R0.6C and ProC6C drug products were found to be stable for minimally 24 months when stored at 2-8 °C, with studies ongoing through 36 months. Together, this data demonstrates the safety and suitability of the L. lactis expression system as well as supports the clinical testing of the R0.6C and ProC6C malaria vaccine candidates in First-In-Human clinical trials.
Host-directed-therapy strategies are warranted to fight tuberculosis. Here we assess the safety and immunogenicity of adjunctive vaccination with the H56:IC31 candidate and cyclooxygenase-2-inhibitor treatment (etoricoxib) in pulmonary and extra-pulmonary tuberculosis patients in a randomized open-label phase I/II clinical trial (TBCOX2, NCT02503839). A total of 222 patients were screened, 51 enrolled and randomized; 13 in the etoricoxib-group, 14 in the H56:IC31-group, 12 in the etoricoxib+H56:IC31-group and 12 controls. Three Serious Adverse Events were reported in the etoricoxib-groups; two urticarial rash and one possible disease progression, no Serious Adverse Events were vaccine related. H56:IC31 induces robust expansion of antigen-specific T-cells analyzed by fluorospot and flow cytometry, and higher proportion of seroconversions. Etoricoxib reduced H56:IC31-induced T-cell responses. Here, we show the first clinical data that H56:IC31 vaccination is safe and immunogenic in tuberculosis patients, supporting further studies of H56:IC31 as a host-directed-therapy strategy. Although etoricoxib appears safe, our data do not support therapy with adjunctive cyclooxygenase-2-inhibitors.
Background: The GMZ2/alum candidate malaria vaccine had an efficacy of 14% (95% confidence interval [CI]: 3.6%, 23%) against clinical malaria over 6 months of follow-up in a phase2b multicentre trial in children 1-5 years of age. Here we report the extended follow up of safety and efficacy over 2 years. Methods: A total of 1849 (GMZ2 = 926, rabies = 923) children aged 12-60 months were randomized to receive intramuscularly, either 3 doses of 100 mu g GMZ2/alum or 3 doses of rabies vaccine as control 28 days apart. The children were followed-up for 24 months for clinical malaria episodes and adverse events. The primary endpoint was documented fever with parasitaemia of at least 5000/mu L. Results: There were 2,062 malaria episodes in the GMZ2/alum group and 2,115 in the rabies vaccine group in the intention-to-treat analysis, vaccine efficacy (VE) of 6.5% (95%: CI -1.6%, 14.0%). In children aged 1-2 years at enrolment, VE was 3.6% (95 %CI: -9.1%, 14.8%) in the first year and -4.1% (95 %CI: -18.7%, 87%) in the second year. In children aged 3-5 years at enrolment VE was 19.9% (95 %CI: 7.7%, 30.4%) in the first year and 6.3% (95 %CI: -10.2%, 20.3%) in the second year (interaction by year, P = 0.025, and by age group, P = 0.085). A total of 187 (GMZ2 = 91, rabies = 96) serious adverse events were recorded in 167 individuals over the entire period of the study. There were no GMZ2 vaccine related serious adverse events. Conclusions: GMZ2/alum was well tolerated. Follow-up over 2 years confirmed a low level of vaccine efficacy with slightly higher efficacy in older children, which suggests GMZ2 may act in concert with naturally acquired immunity. (C) 2021 The Authors. Published by Elsevier Ltd.
Background Chlamydia is the most common sexually transmitted bacterial infection worldwide. National screening programmes and antibiotic treatment have failed to decrease incidence, and to date no vaccines against genital chlamydia have been tested in clinical trials. We aimed to assess the safety and immunogenicity, in humans, of a novel chlamydia vaccine based on a recombinant protein subunit (CTH522) in a prime-boost immunisation schedule. Methods This phase 1, first-in-human, double-blind, parallel, randomised, placebo-controlled trial was done at Hammersmith Hospital in London, UK, in healthy women aged 19-45 years. Participants were randomly assigned (3:3:1) to three groups:CTH522 adjuvanted with CAF01 liposomes (CTH522:CAF01), CTH522 adjuvanted with aluminium hydroxide (CTH522:AH), or placebo (saline). Participants received three intramuscular injections of 85 mu g vaccine (with adjuvant) or placebo to the deltoid region of the arm at 0, 1, and 4 months, followed by two intranasal administrations of 30 mu g unadjuvanted vaccine or placebo (one in each nostril) at months 4.5 and 5.0. The primary outcome was safety and the secondary outcome was humoral immunogenicity (anti-CTH522 IgG seroconversion). This study is registered with Clinicaltrials. gov, number NCT02787109. Findings Between Aug 15, 2016, and Feb 13, 2017, 35 women were randomly assigned (15 to CTH522:CAF01, 15 to CTH522:AH, and five to placebo). 32 (91%) received all five vaccinations and all participants were included in the intention-to-treat analyses. No related serious adverse reactions were reported, and the most frequent adverse events were mild local injection-site reactions, which were reported in all (15 [100%] of 15) participants in the two vaccine groups and in three (60%) of five participants in the placebo group (p=0.0526 for both comparisons). Intranasal vaccination was not associated with a higher frequency of related local reactions (reported in seven [47%] of 15 participants in the active treatment groups vs three [60%] of five in the placebo group; p=1.000). Both CTH522:CAF01 and CTH522:AH induced anti-CTH522 IgG seroconversion in 15 (100%) of 15 participants after five immunisations, whereas no participants in the placebo group seroconverted. CTH522:CAF01 showed accelerated seroconversion, increased IgG titres, an enhanced mucosal antibody profile, and a more consistent cell-mediated immune response profile compared with CTH522:AH. Interpretation CTH522 adjuvanted with either CAF01 or aluminium hydroxide appears to be safe and well tolerated. Both vaccines were immunogenic, although CTH522:CAF01 had a better immunogenicity profile, holding promise for further clinical development.
H1/IC31® is a tuberculosis (TB) subunit vaccine candidate consisting of the fusion protein of Ag85B and ESAT-6 (H1) formulated with the IC31® adjuvant. Previous trials have reported on the H1/IC31® vaccine in M. tuberculosis (Mtb)-naïve, BCG-vaccinated and previously Mtb-infected individuals. In this trial, conducted between December 2008 and April 2010, the safety and immunogenicity of H1/IC31® was assessed in participants living in Ethiopia – a highly TB-endemic area.
CD4 T cells are critical for protective immunity against Mycobacterium tuberculosis (Mtb), the cause of tuberculosis (TB). Yet to date, TB vaccine candidates that boost antigen-specific CD4 T cells have conferred little or no protection. Here we examined CD4 T cell responses to two leading TB vaccine antigens, ESAT-6 and Ag85B, in Mtb-infected mice and in vaccinated humans with and without underlying Mtb infection. In both species, Mtb infection drove ESAT-6-specific T cells to be more differentiated than Ag85B-specific T cells. The ability of each T cell population to control Mtb in the lungs of mice was restricted for opposite reasons: Ag85B-specific T cells were limited by reduced antigen expression during persistent infection, whereas ESAT-6-specific T cells became functionally exhausted due to chronic antigenic stimulation. Our findings suggest that different vaccination strategies will be required to optimize protection mediated by T cells recognizing antigens expressed at distinct stages of Mtb infection.
Background: GMZ2 is a recombinant protein malaria vaccine, comprising two blood-stage antigens of Plasmodium falciparum, glutamate-rich protein and merozoite surface protein 3. We assessed efficacy of GMZ2 in children in Burkina Faso, Gabon, Ghana and Uganda.Methods: Children 12-60 months old were randomized to receive three injections of either 100 mu g GMZ2 adjuvanted with aluminum hydroxide or a control vaccine (rabies) four weeks apart and were followed up for six months to measure the incidence of malaria defined as fever or history of fever and a parasite density >= 5000/mu L.Results: A cohort of 1849 children were randomized, 1735 received three doses of vaccine (868 GMZ2, 867 control-vaccine). There were 641 malaria episodes in the GMZ2/Alum group and 720 in the control group. In the ATP analysis, vaccine efficacy (VE), adjusted for age and site was 14% (95% confidence interval [CI]: 3.6%, 23%, p-value = 0.009). In the ITT analysis, age-adjusted VE was 11.3% (95% CI 2.5%, 19%, p-value = 0.013). VE was higher in older children. In GMZ2-vaccinated children, the incidence of malaria decreased with increasing vaccine-induced anti-GMZ2 IgG concentration. There were 32 cases of severe malaria (18 in the rabies vaccine group and 14 in the GMZ2 group), VE 27% (95% CI -44%, 63%).Conclusions: GMZ2 is the first blood-stage malaria vaccine to be evaluated in a large multicenter trial. GMZ2 was well tolerated and immunogenic, and reduced the incidence of malaria, but efficacy would need to be substantially improved, using a more immunogenic formulation, for the vaccine to have a public health role. (C) 2016 Elsevier Ltd. All rights reserved.
Background: Control of the tuberculosis epidemic requires a novel vaccine that is effective in preventing tuberculosis in adolescents, a key target population for vaccination against TB.Methods: Healthy adolescents, stratified by M. tuberculosis-infection status, were enrolled into this observer-blinded phase II clinical trial of the protein-subunit vaccine candidate, Hl:IC31, comprising a fusion protein (H1) of Ag85B and ESAT-6, formulated with the IC31 adjuvant. Local and systemic adverse events and induced T cell responses were measured after one or two administrations of either 15 tg or 50 tg of the H1 protein.Results: Two hundred and forty participants were recruited and followed up for 224 days. No notable safety events were observed regardless of H1 dose or vaccination schedule. H1:IC31 vaccination induced antigen-specific CD4 T cells, co-expressing IFN-gamma, TNF-alpha. and/or IL-2. H1:IC31 vaccination of M.tb-uninfected individuals preferentially drove the emergence of Ag85B and ESAT-6 specific TNF-alpha IL-2+CD4 T cells, while H1:IC31 vaccination of M.tb-infected individuals resulted in the expansion of Ag85B-specific but not ESAT-6-specific TNF-ix+IL-2+CD4 T cells.Conclusions: H1:101 was safe and immunogenic in uninfected and M.tb-infected adolescents. Two administrations of the 15 tg H1:IC31 dose induced the greatest magnitude immune response, and was considered optimal (South African National Clinical Trials Register, DoH-27-0612-3947; Pan African Clinical Trial Registry, PALS1t201403000464306). (C) 2016 Elsevier Ltd. All rights reserved.
ABSTRACT Tuberculosis (TB) remains a global health problem, with vaccination being a necessary strategy for disease containment and elimination. A TB vaccine should be safe and immunogenic as well as efficacious in all affected populations, including HIV-infected individuals. We investigated the induction and maintenance of vaccine-induced memory CD4+ T cells following vaccination with the subunit vaccine H1/IC31. H1/IC31 was inoculated twice on study days 0 and 56 among HIV-infected adults with CD4+ lymphocyte counts of >350 cells/mm3. Whole venous blood stimulation was conducted with the H1 protein, and memory CD4+ T cells were analyzed using intracellular cytokine staining and polychromatic flow cytometry. We identified high responders, intermediate responders, and nonresponders based on detection of interleukin-2 (IL-2), tumor necrosis factor alpha (TNF-α), and gamma interferon (IFN-γ) expressing central (TCM) and effector memory CD4+ T cells (TEM) 182 days after the first immunization. Amplicon-based transcript quantification using next-generation sequencing was performed to identify differentially expressed genes that correlated with vaccine-induced immune responses. Genes implicated in resolution of inflammation discriminated the responders from the nonresponders 3 days after the first inoculation. The volunteers with higher expression levels of genes involved in antiviral innate immunity at baseline showed impaired H1-specific TCM and TEM maintenance 6 months after vaccination. Our study showed that in HIV-infected volunteers, expression levels of genes involved in the antiviral innate immune response affected long-term maintenance of H1/IC31 vaccine-induced cellular immunity. (The clinical trial was registered in the Pan African Clinical Trials Registry [PACTR] with the identifier PACTR201105000289276.)
Background Novel tuberculosis vaccines should be safe, immunogenic, and effective in various population groups, including HIV-infected individuals. In this phase II multi-centre, double-blind, placebo-controlled trial, the safety and immunogenicity of the novel H1/IC31 vaccine, a fusion protein of Ag85B-ESAT-6 (H1) formulated with the adjuvant IC31, was evaluated in HIV-infected adults. Methods HIV-infected adults with CD4+ T cell counts >350/mm3 and without evidence of active tuberculosis were enrolled and followed until day 182. H1/IC31 vaccine or placebo was randomly allocated in a 5∶1 ratio. The vaccine was administered intramuscularly at day 0 and 56. Safety assessment was based on medical history, clinical examinations, and blood and urine testing. Immunogenicity was determined by a short-term whole blood intracellular cytokine staining assay. Results 47 of the 48 randomised participants completed both vaccinations. In total, 459 mild or moderate and 2 severe adverse events were reported. There were three serious adverse events in two vaccinees classified as not related to the investigational product. Local injection site reactions were more common in H1/IC31 versus placebo recipients (65.0% vs. 12.5%, p = 0.015). Solicited systemic and unsolicited adverse events were similar by study arm. The baseline CD4+ T cell count and HIV viral load were similar by study arm and remained constant over time. The H1/IC31 vaccine induced a persistent Th1-immune response with predominately TNF-α and IL-2 co-expressing CD4+ T cells, as well as polyfunctional IFN-γ, TNF-α and IL-2 expressing CD4+ T cells. Conclusion H1/IC31 was well tolerated and safe in HIV-infected adults with a CD4+ Lymphocyte count greater than 350 cells/mm3. The vaccine did not have an effect on CD4+ T cell count or HIV-1 viral load. H1/IC31 induced a specific and durable Th1 immune response. Trial registration Pan African Clinical Trials Registry (PACTR) PACTR201105000289276
Background: The use of plasma-derived immunoglobulin G (IgG) is increasing, and the number of diseases, including immunodeficiencies, neurological diseases and autoimmune conditions, treated with intravenous IgG (IVIG) is expanding. Consequently, there is a great need for high-yield production processes for plasma-derived IgG. The aim of this work was to develop a high-yield process leading to a highly purified, liquid, ready-to-use IgG for intravenous use. Methods: Plasma from healthy, voluntary, non-remunerated donors was fractionated by ethanol precipitation. IgG was extracted from fraction II + III using a phosphate/acetate buffer, pH 4, and purified by chromatography. Results: Precipitation with 6% polyethylene glycol at pH 7 removed high molecular-weight contaminating proteins, aggregates and contaminating viruses. Ion exchange chromatography at pH 5.7 on serially connected anion and cation exchange columns allowed for elution of IgG from the cation exchange column in good yield and high purity. Further safety was achieved by solvent/detergent treatment and repeated ion exchange chromatography. The product consisted of essentially only IgG monomers and dimers, and had a high purity with very low levels of IgM and IgA. Conclusion: A process providing highly purified IVIG in good yield was developed.
One third of the world’s population is thought to have latent tuberculosis infection (LTBI) with the potential for subsequent reactivation of disease. To better characterize this important population, studies comparing Tuberculin Skin Test (TST) and the new interferon-γ release assays including QuantiFERON®-TB Gold In-Tube (QFT-GIT) have been conducted in different parts of the world, but most of these have been in countries with a low incidence of tuberculosis (TB). The aim of this study was therefore to evaluate the use of QFT-GIT assay as compared with TST in the diagnosis of LTBI in Ethiopia, a country with a high burden of TB and routine BCG vaccination at birth.
Therapeutic immunization of HIV-1-infected individuals with or without anti-retroviral therapy is a new promising disease prevention. To induce a new cytotoxic TCD8 lymphocyte (CTL) immunity during chronic HIV-1 infection 15 infrequently targeted but conserved HLA-supertype binding CTL epitopes from Gag, Pol, Nef, Env, Vpu and Vif were identified. The 15 TCD8 and three TCD4 helper peptides were GMP synthesised and formulated with a new adjuvant CAF01 which is a synthetic two-component liposomic adjuvant comprising the quaternary ammonium dimethyl-dioctadecyl-ammonium (DDA) and the immune modulator trehalose 6,6′-dibehenate (TDB). Using IFN-γ ELISPOT assay, T-cell immune induction by the vaccine was found to both CD4 and CD8 T-cell restricted peptides in HLA-A2 transgenic mice. Comprehensive toxicity studies of the CAF01 adjuvant-alone and together with different vaccines showed that CAF01 when tested at human dose levels was safe and well tolerated with only local inflammation at the site of injection and no systemic reactions. No pharmacological safety issues were observed in Beagle dogs. The HIV-1 vaccine toxicity study in the Göttingen Minipig® showed no systemic toxicity from five repetitive i.m. injections, each with a 2-week interval, of either the 18 HIV-1 peptide antigen solution (AFO18) or the AFO18–CAF01, in which the 18 HIV-1 peptides were formulated with the CAF01 adjuvant. Distinct inflammatory responses were observed in the injected muscles of the AFO18–CAF01 vaccine treated animals as a result of the immune stimulating effect of the adjuvant on the vaccine. The results of the toxicity studies provide optimism for phase I clinical trials evaluating the therapeutic HIV-1 T-cell vaccination approach using multiple subdominant minimal epitope peptides applying the novel cationic adjuvant CAF01.
New TB vaccines are urgently needed because of the apparent lack of effect of the BCG vaccine on rates of adult contagious pulmonary tuberculosis and the risk of disseminated BCG disease in immunocompromised individuals. Since BCG appears to protect children, the primary target for vaccine development is a booster vaccine for adults but such vaccines ideally need to be able to efficiently prime mycobacterially naïve individuals as well as boost individuals previously vaccinated with BCG and those latently infected with TB. Protective immunity against Mycobacterium tuberculosis depends mainly on the generation of a Th1-type cellular immune response characterized by interferon-gamma (IFN-γ) production. In the present study, we monitored safety and IFN-γ responses in healthy BCG-vaccinated and prior or latently TB-infected individuals receiving a novel vaccine composed of the fusion protein Ag85B–ESAT-6 combined with the adjuvant IC31®, administered at 0 and 2 months. Vaccination caused few local or systemic adverse effects besides transient soreness at the injection site, but it elicited strong antigen-specific T cell responses against Ag85B–ESAT-6 and both the Ag85B and ESAT-6 components, that could be augmented by second vaccination. The strong responses persisted through 32 weeks of follow-up, indicating the induction of a persistent memory response in the vaccine recipients.
Despite the extensive success with the introduction of M. bovis Bacille Calmette-Guérin (BCG), tuberculosis (TB) remains a major global epidemic infecting between 8 and 9 million people annually with an estimated 1.7 million deaths each year. However, because of its demonstrated effectiveness against some of the most severe forms of childhood TB, it is now realized that BCG vaccination of newborns is unlikely to be replaced. Therefore, BCG or an improved BCG will continue to be used as a prime TB vaccine and there is a need to develop effective boost vaccines that would enhance and prolong the protective immunity induced by BCG prime immunization. We report on a heterologous booster approach using two highly immunogenic TB antigens comprising Ag85B and TB10.4 (HyVac4) delivered as a fusion molecule and formulated in the proprietary adjuvant IC31. This vaccine was found to be immunogenic and demonstrated greater protection in the more stringent guinea pig model of pulmonary tuberculosis than BCG alone when used in a prime/boost regimen. Significant difference in lung involvement was observed for all animals in the HyVac4 boosted group compared to BCG alone regardless of time to death or sacrifice. A vaccine toxicology study of the HyVac4:IC31 regimen was performed and it was judged safe to advance the vaccine into clinical trials. Therefore, all non-clinical data supports the suitability of HyVac4 as a safe, immunogenic, and effective vaccination in a prime-boost regimen with BCG.
Tuberculosis (TB) remains a major killer worldwide. The only available TB-vaccine, the nearly century-old Mycobacterium bovis BCG, has had only a limited effect on TB incidence. Therefore, developing new TB vaccines is a key priority, and the first new generation TB vaccines are now being tested in clinical trials. Here we describe the development and first testing in humans of a novel, wholly synthetic TB subunit vaccine. This vaccine has proven safe and highly immunogenic in all species in which it was tested, including mice, guinea pigs, non-human primates and humans. Most encouragingly, following vaccination in humans, strong IFN-γ responses persisted through at least 2½ years of follow-up, indicating induction of a substantial memory response by this new TB vaccine. These findings encourage further preclinical and clinical studies with TB subunit vaccines and cellular immunity-stimulating new adjuvants.
Mannan-binding lectin (MBL) is a member of the innate immune system, and MBL-deficiency affects 10-15% of Caucasians. With development of a plasma-derived MBL, substitution has become a therapeutic option in diseases associated with MBL insufficiency. The pharmacokinetics of injected MBL is weakly described, particularly in patients with infectious diseases. The pharmacokinetic profile of MBL following administration of 0.08 mg/kg to 20 healthy MBL-deficient volunteers and 0.2 mg/kg to 2 patients with Staphylococcus aureus septicaemia was established. In the volunteers, the maximal concentration was 2849 microg/l; the mean half-life (T(1/2)) was 69.6 h (14.6-114.9 h). The normalized clearance was 9x10(-6) l/minxkg, and the mean residence time was 82 h. In the patients the serum-MBL versus time curves were similar to those in the volunteers, and T(1/2) values were 36 and 40 h. In conclusion, MBL is distributed into a median volume of 3.4 l similar to the plasma volume, and the elimination in septicaemic patients was within the range of the controls. Due to the large individual variation in T(1/2), we recommend that MBL therapy, with respect to dose and infusion intervals, is based on the chosen therapeutic target (> or =1000 microg/l) and MBL serum determinations following the first infusion.
Objective: To investigate if IV immunoglobulin ( IVIG) treatment in the acute phase of optic neuritis ( ON) could improve visual outcome and reduce MRI disease activity 6 months after onset of ON. Methods: Sixty-eight patients with ON were randomized within 4 weeks from onset of symptoms. Thirty-four patients were randomized to IVIG 0.4 g/kg body wt, and 34 patients were randomized to placebo. Infusions were given at days 0, 1, 2, 30, and 60. Contrast sensitivity, visual acuity, and color vision were measured at baseline and after 1 week, 1 month, and 6 months. Pattern reversal visual evoked potential studies and gadolinium-enhanced MRI were performed at baseline and after 1 and 6 months. Clinical relapses during follow-up were recorded. Results: There was no difference in the primary outcome, contrast sensitivity after 6 months, between patients randomized to treatment with IVIG or placebo. In addition, there was no significant difference in the secondary outcome measures, improvement in the visual function measures and MRI, at any time during follow-up. At baseline, a significantly higher number of patients in the IVIG group had one or more enhancing lesions on MRI and IVIG-treated patients had a significantly higher number of enhancing lesions on MRI than patients treated with placebo. No difference was found in number of patients with one or more enhancing lesions or number of enhancing lesions in subsequent scans between treatment groups. Number of relapses was equal in the two treatment groups during follow-up. Conclusions: There was no effect of IV immunoglobulin (IVIG) on long-term visual function following acute optic neuritis, nor was there an effect of IVIG treatment in reducing latency on visual evoked potentials and thus preserving function of axons of the optic nerve.